1. Field of the Invention
The present invention relates to a motor structure, and more particularly to a miniature motor structure.
2. Description of the Prior Art
As shown in FIG. 1, the stator structure of a conventional miniature motor includes an upper silicon steel 10, a bearing tube 20, a lower silicon steel 30 and a coil 40. Among these, the upper silicon steel 10 and the lower silicon steel 30 are annular in shape. Besides, there are upper side plates or lower side plates extending upward or downward from the outer periphery of the upper silicon steel 10 and the lower silicon steel 30. The cylindrical bearing tube 20 provides a rivet joint so as to joint the upper silicon steel 10, the coil 40 and the lower silicon steel 30 together. Further, the coil 40 is sandwiched between the upper silicon steel 10 and the lower silicon steel 30.
The disadvantage of the conventional miniature motor at least includes that the bearing tube 20 providing a rivet joint is required for jointing the upper silicon steel 10, the coil 40 and the lower silicon steel 30 together. That is, the conventional miniature motor is not easy to fabricate.
The present invention discloses a miniature motor structure omitting the prior bearing tube described above to reduce cost and simplify the required fabricating process.
The present miniature motor structure includes a first coil seat, second coil seat, a coil, a circular magnet, a metal housing and a shaft. The first coil seat includes a first bottom plate, a plurality of first outer teeth and a plurality of first inner teeth. The first bottom plate further includes a first central opening. The first outer teeth protrude from the first bottom plate and surround the outer periphery of the first bottom plate. The first inner teeth protrude from the first bottom plate and surround the first central opening. Further, the coil is positioned in the first coil seat.
The second coil seat includes a second bottom plate, a plurality of second outer teeth and a plurality of second inner teeth. The second bottom plate further includes a second central opening. The second outer teeth protrude from the second bottom plate and surround the outer periphery of the second bottom plate. The second inner teeth protrude from the second bottom plate and surround the second central opening.
The second bottom plate of the second coil seat is formed above the coil and the first coil seat. Besides, each of the second outer teeth is interposed between the adjacent first outer teeth. Each of the second inner teeth is interposed between the adjacent first inner teeth. In this manner, the first coil seat and the second coil seat define a space accommodating the coil. In addition, the first inner teeth and the second inner teeth form a post for winding the coil. By means of the first inner teeth and the second inner teeth, the first coil seat and the second coil seat are coupled to each other. In the preferred embodiment, both of the first coil seat and the second coil seat are made of silicon steel. However, other magnetic conduction material, such as nickel steel, is applicable to the first coil seat and the second coil seat. The coil may be a preformed coil. Alternatively, the coil may be the coil wound around the post.
The first coil seat, the second coil seat and the coil construct the stator of the present invention. The first coil seat and the second coil seat may be identical to each other. That is, the stator may be composed of a first coil seat, an upside-down first coil seat and a coil. However, the first coil seat may be different from the second coil seat. Besides, the first coil seat and the second coil seat are made of sheet metal.
In order to advantageously adjust the angle of magnetic inclination to start the motor, the outer teeth optionally includes a cut corner, an arc and a gap may extending from the outer teeth to the bottom plate.